The present invention relates to a high-frequency treating instrument for an endoscope which is passed through the treating instrument insertion channel of the endoscope so as to perform a transendoscopic mucous membrane exfoliation operation etc.
In the case of performing a transendoscopic mucous membrane exfoliation operation, in general, physiological saline solution etc. is injected under a mucous membrane to be exfoliated to raise the mucous membrane, and the periphery of the raised portion is resected by a high-frequency treating instrument etc. for an endoscope which tip end portion is bent in a hook shape (see patent documents 1, 2 and 3, for example).
Patent Document 1: JP-A-2002-153484
Patent Document 2: JP-A-6-292685
Patent Document 3: JP-A-5-293115
In the aforesaid related high-frequency treating instrument for an endoscope, although it is possible to resect the raised mucous membrane portion in a manner of surrounding the portion, it is difficult to exfoliate the raised mucous membrane portion from the tissue under the portion. Thus, it is required to withdraw the treating instrument for the resecting operation from the treating instrument insertion channel of the endoscope after the resecting operation, then an exfoliation instrument etc. for the endoscope of a spatula shape is inserted into the resected portion in place of the treating instrument for the resecting operation to exfoliate the mucous membrane portion from a sinew layer under the mucous membrane portion. Thus, since the exfoliation operation is complicated, such an operation is heavy burden for an operator and a patient.
Thus, in order so that both the mucous membrane resecting operation using a high-frequency current and the mucous membrane exfoliation operation succeeding thereto are performed by using a single treating instrument, it is considered to form a high-frequency electrode in a spatula shape such as a rice scoop.
However, when the high-frequency treating instrument is simply formed in the spatula shape such as a rice scoop, a mechanical hooking force thereof with respect to a mucous membrane is small. Thus, at the time of the mucous membrane resecting operation, when the high-frequency electrode is moved within a mucous membrane while it is cut into the mucous membrane, there may arise a case that the high-frequency electrode slides with respect to the mucous membrane and so rises above the surface of the mucous membrane, whereby the mucous membrane can not be resected smoothly.